https://devzone.nordicsemi.com/f/nordic-q-a/129467/nrf54l15-cs-with-ipt-softdevice-controller-assert-142-151-and-concurrent-multi-connection-cs-with-iptHello Nordic team, I&#39;m running Channel Sounding for ranging and localization research with two nRF54L15 DKs. I compared the Ranging Service (RAS) with IPT using ras_initiator/ras_reflector and ipt_initiator/ipt_reflector samples. I have two questionsen-USTelligent Community 13Thu, 22 Oct 2026 13:23:39 GMThttps://devzone.nordicsemi.com/thread/572517?ContentTypeID=1Thu, 22 Oct 2026 13:23:39 GMT137ad170-7792-4731-bb38-c0d22fbe4515:29e2b0f7-fec4-45dc-aae7-22d1188064aaSimonr<p>Hi</p> <p>1.</p> <p>a) The 142, 151 assert points to an assert when updating the length of a Channel Sounding subevent. So it could be the <strong>max_procedure_len</strong> that times out or the <strong>subevent_counter</strong> that is invalid.</p> <p>b) There are quite a few improvements to our Channel Sounding libraries there.&nbsp;<a href="https://github.com/nrfconnect/sdk-nrfxlib/blob/v3.4.1/softdevice_controller/CHANGELOG.rst#bug-fixes">https://github.com/nrfconnect/sdk-nrfxlib/blob/v3.4.1/softdevice_controller/CHANGELOG.rst#bug-fixes</a>&nbsp;</p> <p>c) That does not seem to match this assert. Then I&#39;d assume you get a buffer overflow reported somewhere instead.</p> <p>2.&nbsp;</p> <p>It should be possible to do multiple rangings, but again, this has not been extensively tested on our end, and users are expected to handle the scheduling. I would recommend moving to NCS v3.4.1 and do sequential ranging with one initiator and multiple reflectors, as the initiator can then handle the connections and synchronizations easier and finish one measurement before polling the next device.</p> <p>Best regards,</p> <p>Simon</p><div style="clear:both;"></div>